It is the objective of the proposed research: a) to advance knowledge on the biogenetic origin of a C7N unit which can be discerned in the mitomycin antibiotics and which presumably arises from an intermediate of the shikimic acid pathway; b) to further explore the role of D-glucosamine in the biosynthesis of a C6N unit discernible in the mitomycins and; c) to obtain information on the nature and on the formation of intermediates of mitomycin biosynthesis. These goals will be pursued in feeding experiments with isotopically labeled compounds, many of which will be synthesized, and they will be pursued in experiments with cell-free extracts of the mitomycin producing organism -Streptomyces verticillatus. Cell-free studies will also be undertaken to gain information on the regulation of the formation and on the metabolism of essential precursors. Studies on the origin of the C7N unit appear to be of particular interest since the ansamycin antibiotics rifamycin, streptovaricin and geldenamycin as well as a number of other antibiotics from Streptomycetes appear to share with the mitomycins the origin of similar C7N units from an intermediate of the shikimic acid pathways. The presumed common biogenetic origin of these C7N units suggests that such units are of major importance in the biochemistry of Strptomycetes. Further studies on the origin of the C6N unit appear to be of interest because recent results have provided evidence suggesting the possibility that D-glucosamine undergoes a cleavage into a C3N and a C3 unit which can equilibrate prior to incorporation into mitomycins. This cleavage of D-glucosamine appears to be without precedence, and indicates that presence in S. verticillatus of a novel pathway of glucosamine metabolism.